- 1

- UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX AIR DIVISION

Technical Support Document

f or the

Gila River Indian Community Tribal Implementation Plan

___________________________________________________________

Ju ly 2010

Prepare d by :

Sona Chilingaryan

Francisco Donez Roger Kohn

Nicole Law

Al Petersen Stanley Tong

Wienke Tax Jerry Wamsley Mae Wang

Joanne Wells- 2

-

Table of Contents

I

. Introduction

II. Permit Requirements

I II. Area Source Emission Limits

A. Open Burning

B. Fugitive Dust

I V

. Generally Applicable Individual Source Requirements for Existing and New Sources

A. Visible Emissions

B. Volatile Organic Compound Storage, Usage, and Handling

C. Degreasing and Solvent Metal Cleaning

V . Source/Category

- S pecif ic Emission Limits for Existing and New Sources

A. Secondary Aluminum Facilities

B. Aerospace Manufacturing

C. Nonmetallic Mineral Processing- 3

-

I

. Introduction

Generally, the rules in a Clean Air Act (CAA) implementation plan must be

enforceable (see s ection 110(a)) and must not relax existing plan requirements (see

s ections 110(l) and 193). Because there is no existing EPA

- approved implementation plan in the Gila River Indian Community (GRIC) reservation, sections 110(l) and 193 do not apply t o this action.

The GRIC r eservation is located in south

- central Arizona, adjacent to the Phoenix Metropolitan Area, in Pinal and Maricopa Counties. The entire reservation is designated attainment or unclassifiable/attainment for the following NAAQS pollu tants: lead (Pb), carbon monoxide (CO), nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), particulate matter of 2.5 microns or less (PM 2.5 ), and ground

- level ozone. 40

CFR 81.303. As such, for all of these pollutants, the requirements of part D, title I of the Act ( e.g., RACT) do not apply in the GRIC reservation

.

The only criteria pollutant for which a portion of the reservation is currently designated nonattainment is PM 10

. Approximately 92,000 acres of the GRIC reservation, along its northern boundary, lie within the Maricopa County (Phoenix Planning Area) serious PM 10 nonattainment area. Se e 52 FR 29383, ( August 7, 1987) ; 61 FR 21372 (May 10, 1996) (reclassification to serious nonattainment effective June 10, 1996). The remainder of the GRIC reservati on is located in the portion of Pinal County that is currently designated as unclassifiable/attainment for PM 10 . 40 CFR 81.303. The regulations in the TIP are enforceable and function independently of the

PM 10 nonattainment area requirements of subpart 4 of part D, title I of the Act

. As such, the TIP regulations are reasonably severable from these part D requirements

. 40 CFR 49.7(c). Therefore

, we are not evaluating the TIP for compliance with any part D requirements, such as the requirement for Best Available Control Measures (BACM) in CAA § 189(b).

The following document provides USEPA Region 9 ’s evaluation of specific rules

included in the GRIC ’s Tribal Implementation Plan (TIP), which is codified in Title 18, Chapter 7 of the GRIC Code.

II. Permit Requirements

We are proposing to approve the minor source permit program in Part II as a base program suitable to the GRIC’s reservation , as discussed below

.

Program Summary

Part II of the TIP contains a p ermit program for minor sources t hat includes requirements for preconstruction review, stack height limitations, continuous source emissions monitoring requirements, requirements for confidentiality of information, and permit fee provisions (Sections 1.0, 2.0, 4.0, 5.0, 6. 0, 9.0 , 10.0, 11 .0). We are proposing to act only on those elements of Part II that constitute a minor source- 4

-

permit program under CAA 110(a)(2)(C).

Program Evaluation

The minor source permit program sets forth legally enforceable procedures that

enable the GRIC to det ermine whether the construction or modification of a facility, building, structure or installation, or combination of these will result in interference

with attainment or maintenance of a NAAQS in the GRIC reservation or in a neighboring State , and include s the administrative procedures for making these determinations. The procedures enable the GRIC to prevent construction where such

interference will occur . The procedures also require the GRIC to provide opportunity for public comment on information sub m itted by owners and operators, the GRIC’s analysis of the effect of construction or modification on ambient air quality , and the proposed approval or disapproval. T he program identifies the GRIC DEQ as the agency which will be responsible for implementing these requirements throughout the

reservation. These provisions meet the minimum requirements of 40 CFR 51.160

- 51.163 as applied to the GRIC reservation and the particular mix of sources under the GRIC DEQ’s jurisdiction

. For a more detailed explanation of the permit procedures and air quality goals that the permit program addresses

, s ee Letter dated June 22, 2009, from Margaret Cook, Executive Director, GRIC DEQ, to Laura Yoshii, Acting Regional Administrator, EPA Region 9, “Re: Technical Corrections to the GRIC Air Quality Management Plan,” enclosure entitled “Minor New Source Review

Demonstration.”

Section 6.0 contains requirements for continuous s ource e missions m onitoring. These requirements are not fully equivalent to the provisions of 40 CFR pa rt 51, appendix P (“Minimum Emission Monitoring Requirements”) , but they are generally consistent with appendix P requirements and acceptable for purposes of a minor source permit

program. We are not proposing to approve these provisions as meeting the

re quirements of 40 CFR 51.165 or appendix P or for purposes of any other requirement applicable to major stationary sources

. We provide recommendations for rule improvement further below.

Section 9.0 contains stack height provisions that require that “[t] h e degree of emission limitation required of any source . . . for control of any pollutant shall not be affected by so much of any sources stack height that exceeds good engineering practice or by any other dispersion technique. ” Before the

GRIC DEQ issue s a permit or permit revision to a source based on a good engineering practice (GEP) stack height that exceeds the height allowed under Section 9.0 , GRIC DEQ must notify the public of the availability of the demonstration study and provide

an opp ortunity f or a public hearing

. These provisions meet the applicable requirements for stack heigh t procedures in 40 CFR 51.164.

Finally, Sections 10.0 and 11.0 establish requirements for confidentiality of information and permit fees. CAA 110(a)(2)(C) and 40 CFR p art 51, subpart I do not establish specific requirements for confidentiality of information or permit fees in a- 5

-

minor source permit program. We conclude that these TIP provisions are acceptable.

Recommendations for Rule Improvement

 Per the GRIC DEQ’s re quest by letter dated June 22, 2009, EPA is not proposing to

act on the waiver provision in section 4.4.B as part of the TIP

. To avoid confusion,

w e recommend that the GRIC formally amend the AQMP to remove this provision

under Tribal law as well

.

 P er t he GRIC DEQ’s request by letter dated June 22, 2009, EPA is not proposing to act on the title V provisions of Part II as part of the TIP . To avoid confusion, w e recommend that the GRIC formally amend the AQMP to remove all title V and major source provisi ons from Part II, so that it contains only those non

- title V (minor source) permit requirements that are part of the EPA

- approved TIP. This will require corresponding revisions to different sections of Part II, including the

definitions in section 1.0 and the permit fee provisions in section 11.0.

 S ection 1.0 defines “major modification” to include projects that are subject only to the GRIC’s minor NSR program (i.e., not to Fede ral major NSR requirements). We recommend using a different term to refer to modifications subject only to the GRIC’s minor NSR program, as this us e of a Federally

- defined term could cause

confusion

.

 Section 4.2 requires that t he BRDT control standard apply to any “new non

- title V

sourc e ” that ha s a potential to emit (PTE) at least 75 tpy of any criteria pollutant, and to any modification project that results in a PTE increase of at least 25 tpy of any criteria pollutant

. We recommend that the GRIC consider lowering th e BRDT

threshold for new sources, as a 75 tpy threshold may allo w fairly large sources to avoid installing pollution controls during initial construction, which is generally the point at which a source can install control s most cost

- effectively

.

 S ection 4.4.A.1 establishes a permit term of 5 years for non

- title V permi ts. We note that although EPA’s title V regulations establish a 5

- year term for title V operating permits, preconstruction permits generally should not expire. We recommend that GRIC consider removing this provision or adding a n application

shield provis ion (similar to the title V application shield) for sources that submit timely and complete renewal applications

.

 T he permit revision requirements in section 5.0 remain potentially confusing and

EPA commits to work with the GRIC to clarify these provisions as soon as possible

. For example, the relationship (if any) and distinctions between the “permit revision” requirements in section 5.1 and the “significant permit revision” requirements in section 5.5 should be clarified.

 S ection 4.6.D appears to require the GRIC DEQ to hold a public hearing upon request. To avoid undue administrative burdens, we recommend that GRIC consider revising this provision to provide the GRIC DEQ with discretion to grant or deny a hearing request based on the level of public int erest.

As to Section 6.0 (“Continuous Source Emissions Monitoring”), w e have the following recommendations for rule improvement:- 6

-

 In Section 6.4 Minimum Specifications for Monitoring Equipment, in paragraph

6.4.A.1 “the Administrator” in line 6 of this se ction (paragraph 1) should be

“reference method

. ”

 In Section 6.4 Minimum Specifications for Monitoring Equipment, in paragraph 6.4.A.1.b, we recommend GRIC add the phrase “Appendix B of 40 CFR Part 60” to the end of this subparagraph.

 In Section 6.4 Minimu m Specifications for Monitoring Equipment, in paragraph 6.4.B, calibration gases, “(as amended)” should be deleted and the relevant date

inserted.

 In Section 6.4 Minimum Specifications for Monitoring Equipment, paragraph 6.4.C requires that CEMS for measur ing opacity complete a minimum of one (1) cycle of sampling and analyzing for “each successive 6

- minute period.” We recommend that GRIC revise this to require completion of a minimum of one cycle of operation (sampling, analyzing, and data recording) for “each successive 10

- second period,” consistent with the requirements of section 3.4 of 40 CFR part 51, appendix P.

 In Section 6.4 Minimum Specifications for Monitoring Equipment, in paragraph 6.4.E on combined effluents, this paragraph should be revised t o clarify that the effluent needs to be monitored at the point of discharge.

 In Section 6.4 Minimum Specifications for Monitoring Equipment, in paragraph 6.4.F, “Zero and drift”, we recommend including certain language from EPA’s 40 CFR part 51, Appendix P , Minimum Emission Monitoring Requirements, that has

been omitted

.

 In Section 6.5 Minimum Data Requirement, in paragraph 6.5.B the word “deleted” should be changed to “considered”, consistent with Appendix P.

 In Section 6.6, Data Reduction, in paragraph 6. 6.A, the calculation of pollutant concentration and oxygen concentration in the flue gas should be made on a dry basis. The Director may approve an alternative procedure on a case by case basis for calculating on a wet basis.

II I

. Area Source Emission Li mit s

We are proposing to approve the emission limits for area sources in Part V of the GRIC

TIP as meeting the enforceability requirements of CAA section 110(a)(2)(A), as

discussed below.

A. Open Burning

Rule Summary

Part V, Section 1.0 generally prohibits open burning but cites exceptions for certain types of fires that are authorized with a burn permit and exemptions for certain types

of fires that do not require a burn permit.

Rule Evaluation- 7

-

The evaluation criteria are primarily a comparison of Part V , Section 1.0 to open burning regulations from the Arizona Administrative Code, Section R18

- 2

- 602 Unlawful Open Burning and rules from other air districts and the reasonableness of the exception or exemption in the GRIC area.

Rules used for comparison inc lude Maricopa County Rule 314 and Pinal County Article 8, Open Burning (3

- 8

- 700). Both of these rules have been approved into the Arizona SIP by EPA.

Upon review, we have determined that Part V , Section 1.0 contains specific, well

defined requirements th at meet our enforceability criteria for approval . The rule provides adequate restrictions for open burning, identifies activities requiring a burn permit and activities that are exempt from the rule’s requirements, and does not

allow for variations from the rule other than those specified in the exemptions.

Recommendations for Rule Improvement

The following revisions are currently not the basis for rule disapproval, but are

recommended for the next time the rule is amended.

1. For clarity

, add the defi nition for “Agricultural Burning” in Section 2.0. See definition in Pinal County regulation 3

- 8

- 700.B. ( Definitions ) for Agricultural Burning.

2. Review and expand list of prohibited materials (Section 3.3) as compared with

list s found in other state and loca l rules.

3. For permitted residential fires (Section 3.4 A), include a statement regarding the prohibition of burning residential trash or other prohibited materials along with burning of vegetation and yard waste. Also, include a statement that

material mus t be generated only from that residential property. See definition of “Residential burning” in Pinal County Regulation 3

- 8

- 700 B.

4. F or improved rule clarity on permitted commercial fires, distinguish between

one

- time commercial land clearing operations and commercial fires of vegetative waste such as leaves, lawn clipping, etc. See Pinal County Regulation 3

- 8

- 700, Section C. 2.a & d for example of separating the two

different activities.

5. Define “ other large scale permitted fires ” s o it is clear what type of bur ning is

allowed under this category (Section 3.4 B).

6. Include “commercial” in list of t hose needing to apply for burn permits (section 4.1.A) since a burn permit for commer cial burning is also required.

7. To strengthen safety and burn control requirement s for all burning (Section 4.1 B.) add requirements that fire must be constantly attended with reasonable control tool on hand and that the burn pit or pile be at least 50 feet from

nearest other dwellin g unit or structure. See Pinal County Article 8. Open Burning Rule Section D. 5. Burn Management Provisions.

8. To strengthen safety and burn control requirements

, expand applicability of Section 4.1 C to agricultural burning, with the exception of permit fee, if fee is- 8

-

not applicable to agricultural burning. These requirements are typically applied to agricultural burning by other air district rules

.

B. Fugitive Dust

Rule Summary

Part V , Section 2.0 is designed to limit the emissions of fugitive dust or particulate matter from a variety of activities and sources such as construction sites, bulk material hauling, storage piles, and unpaved parking lots. Rule pro visions include a 20 percent opacity limit as well as specific control measures to reduce particulate

matter emissions from covered activities. Fo r most facilities, developing, implementing, and maintaining a dust control plan sufficient to meet the 20 percent opacity limit will provide the means for demonstrating ongoing compliance.

Rule Evaluation

Upon review, we have determined that Part V , S e ction 2.0 contains specific, well

defined requirements that meet our enforcea bility criteria for approval. The rule provides adequate test methods for compliance determinations, identifies activities that are exempt from the rule’s requirements, and does n ot allow for variations from the rule other than those specified in the exemptions. The rule also requires adequate recordkeeping for demonstrating compliance.

Specifically, we compared this rule with other fugitive dust rules incorporated into

the Calif ornia and Arizona State Implementation Plans such as San Joaquin Valley Air Pollution Control District Regulation 8

– Fugitive PM Prohibitions (adopted 8/19/04 and 9/16/04) and Maricopa County Rule 310

– Fugitive Dust Sources (adopted 2/16/2000). Part V

, Section 2.0 most closely resembles Maricopa County Rule 310 in

form and substance. We approved Maricopa County’s Rule 310 into the Arizona SIP in

2002.

Recommendations for Rule Improvement

We have two suggestions for future revisions to the rule that do not affect our ability to approve the rule. First, the rule should add a provision requiring Title V facilities to keep records available for five years. Second, given that the rule allows for re

establishing vegetative cover as a permanent stabilizatio n strategy, the rule should incorporate test methods for determining vegetative cover.

I V . Generally Applicable Individual Source Requirements for Existing and New

Sources- 9

-

We are proposing to approve t he general prohibitory rules for existing and new

sou rces in Part V I of the GRIC TIP as meeting the enforceability requirements of CAA section 110(a)(2)(A), as discussed below.

A . Visible Emissions

Rule Summary

Part VI , Section 1.0 prohibits the discharge into the ambient air from any single

source of em issions, other than uncombined water, in excess of 20 percent opacity.

Rule Evaluation

When compared with other local air district rules and the State of Arizona Administrative Code, this rule utilize s the same 20 percent opacity limit for discharges int o the ambient air. The State’s 20 percent opacity limit can be found in

Arizona Rules at R18

- 2

- 702 (B) . Maricopa County Rule 300 and Pinal County Rule 2

- 8

- 300 also have a 20 percent opacity limit for visible emissions. This rule also specifies

the EPA test method for compliance determination s , which makes it enforceable. T he

GRIC rule is useful in enforcement as a quick visual indication of compliance

.

Recommendations for Rule Improvement

The following revision is currently not the basis for rule disappr oval, but is

recommended for the next time the rule is amended.

1. The definition in Section 2.0 for Visible Emissions should be amended to include gaseous emissions in addition to particulate emissions, see San Joaquin Valley

Unified Air District Rule 4101

, Visible Emissions.

2. Remove the definition for “Intermittent Source” and Compliance and Test

Method 4.2 “Test Methods

- Opacity of Visible Emissions from Intermittent Sources” since there is no separate opacity standard or exception for

Intermittent Sources in the rule.

3. Remove any exceptions that do not have a current operating source in the GRIC area. This will avoid confusion and improve clarity of requirements.

B. Volatile Organic Compound Storage, Usage, and Handling

Rule Summary

Part VI, Sectio n 2.0 limits the discharge from operations involving heat to 15 pounds per day per device or operations using non

- complying solvents to 40 pounds per day per device. If these limits are exceeded, one must control emissions with at least 85 percent overall efficiency. Certain control techniques are required for VOC- 10

-

containment and disposal. Specifications are provided for the storage of VOC in tanks over 40,000 gallons and in tanks of 250 to 40,000 gallons. Specifications are provided for vapor collection and vapor disposal for loading of VOC with a throughput of over 40,000 gallons per day or less than 40,000 gallons per day.

Rule Evaluation

The evaluation criterion is primarily a comparison to the limits, specifications, and control techniques used in other Districts for handling VOC.

Recommendations for Rule Improvement

Gasoline would be included in the definition of “VOC” given in the October 4, 2006 version of the rule. However, it is not clear whether the rule applies to the loading and storage of gasoline. This should be made clear in order to improve clarity and enforceability.

C. Degreasing and Solvent Metal Cleaning

Rule Summary

Part VI, Section 3 .0 applies to all new and existing solvent cleaning operations using volatile organic compou nds (VOC) for solvent cleaning, including cold cleaning degreasers, open

- top vapor degreasers, and conveyorized degreasers. The rule exempts solvent cleaning operations regulated by another Section in Part VI, laundering and housekeeping supplies and activ ities, testing for surface cleanliness or the cleaning of laboratory equipment at a laboratory, and cleaning solutions containing twenty (20) percent or less VOC by either weight or volume.

The rule includes equipment and operating requirements. Instead of meeting certain equipment requirements, operators of open

- top vapor degreasers and conveyorized degreasers are allowed to meet the standards of the rule through the use of an

Emission s Control System (ECS). Owners or operators of solvent cleaning busine sses that were in operation on or after November 1, 2004 are required to submit an Operation and Maintenance (O & M) Plan for the ECS.

Rule Evaluation

The Bluebook ( Issues Relating to VOC Regulation Cutpoints, Deficiencies, and

Deviations , EPA, May 25, 1988) and the Little Bluebook ( Guidance Document for Correcting Common VOC & Other Rule Deficiencies, EPA Region 9, August 21, 2001) were used to help evaluate the rule for enforceability.

In addition , EPA’s Control of Volatile Organic Emissions from So lvent Metal Cleaning (November 1977) and the California Air Resources Board’s (CARB) Determination of Reasonably Available Control Technology and Best Available Control Technology for- 11

-

Organic Solvent Cleaning and Degreasing Operations (July 18, 1991 ) were used to evaluate rule stringency

.

Recommendations For Rule Improvement

The following revision is currently not the basis for rule disapproval, but is

recommended for the next time the rule is amended.

Section 6.1(E) allows the owner or operator of a c onveyorized degreaser to meet the requirements of Section 6.1 by operating an ECS in accordance with Section 7 of the Rule. Section 7, however, does not specify an overall control efficiency for the ECS. Specifying an overall control efficiency could impro ve both the rule’s stringency and enforceability. For example language, s ee Maricopa Rule 331 Appendix IV. 1.

V . Source/Category

- S pecific Emission Limits for Existing and New Sources

We are proposing to approve t he source c ategory

- s pecific e mission l im its for existing

and new sources in Part V I I of the GRIC TIP as meeting the enforceability requirements of CAA section 110(a)(2)(A), as discussed below.

A. Secondary Aluminum Facilities

Rule Summary

Part VII, Section 1 .0 covers all new, existing and mo dified secondary aluminum facilities located in the Gila River Indian Community.

The rule incorporates by reference the requirements contained in 40 C.F.R. Part 63, Subpart RRR, National Emission Standards for Hazardous Air Pollutants (NESHAPs) for

Seco ndary Aluminum Production. Subpart RRR contains emission limits for dioxins and furans and other hazardous air pollutants that may formed during the smelting of aluminum scrap. Subpart RRR also contains requirements for the testing, monitoring,

recordkee ping, reporting, and labelling of process equipment used in the secondary aluminum production industry to ensure compliance with the regulations.

In addition to the requirements in Subpart RRR, GRIC’s rule sets a 20% opacity limit from any emission sourc e and establishes that volatile organic compound (VOC) emissions be reduced by three (3) percent each year from an established baseline emission rate for a total of five (5) years. Future annual reductions are not required if a facility achieves the requi red 15%VOC reduction early.

The rule requires any owner or operator using an emissions control system to reduce emissions, to submit to GRIC for approval, an operation and maintenance plan. The plan shall specify key system operating parameters such as temperatures, pressures, or flow rates necessary to determine compliance with the requirements. The plan is also required to contain detailed procedures to maintain emission control systems.- 12

-

The rule further requires facilities to install, maintain, cali brate, and operate monitoring devices for operations involved in incinerating, adsorbing, or otherwise processing organic materials.

Rule Evaluation

The following criterion was used to evaluate the submitted rule.

Enforceability

- The Bluebook ( Issue s Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations , EPA, May 25, 1988) and the Little Bluebook ( Guidance Document for Correcting Common VOC & Other Rule Deficiencies, EPA Region 9, August 21, 2001) were used to help evaluate compliance wi th the CAA 110(a)(2)(A) requirement for enforceability.

The submitted rule is more stringent than EPA ’ s National Emission Standard for Secondary Aluminum Production as it incorporates the national standard and adds additional requirements such as opacit y limits and VOC reduction requirements for secondary aluminum facilities. The monitoring, recordkeeping, reporting and other requirements generally ensure that the submitted rule can be enforced.

GRIC submitted a technical support document (TSD) for th is rule that was originally drafted in October 2000. As such, much of the discussion in GRIC’s TSD on the non

applicability of the Secondary Aluminum NESHAPs to area sources and the application of the term “clean charge” are no longer correct.

For exam ple, the NESHAPs require secondary aluminum production facilities which

melt non

- clean scrap to conduct a dioxin/furan emissions test. This test is required whether or not a facility emits more than 10 tons of any single hazardous air pollutant (HAP) or 2 5 tons of any combination of HAPs, and is used to determine compliance with the NESHAPs’ dioxin/furan emission limit. GRIC’s TSD, however, states that one of their facilities, an extruder, is exempt from the NESHAPs because it is a minor source of HAPs (i .e., area source) and melts only clean charge.

Further, EPA has narrowly defined “clean charge” as “scrap known by the owner or operator to be entirely free of paints, coatings, and lubricants...” (40 C.F.R. 63.1503). A source test report from the facility indicated they purchase scrap with lubricants and melts that scrap into round ingots of various lengths and diameters. The extruder is not exempt from the NESHAPs because it melts scrap which does not meet the NESHAPs definition of “clean charge”.

Becau se GRIC’s rule incorporates the Secondary Aluminum NESHAPs as published in the July 1, 2006 version of Title 40 of the Code of Federal Regulations, Part 63, subpart RRR, EPA did not rely on those portions of GRIC’s TSD written in 2000 that differ from

the NESHAPs. The other portions of GRIC’s TSD provide useful background information

on the aluminum industries in Gila River.- 13

-

Recommendations for Rule Improvement

The following rule improvements are provided for evaluation.

Reporting and recordkeeping req uirements. Paragraph 2.2 requires facilities to demonstration annually by February 15, that VOC emissions were reduced by at least three percent of the VOC b aseline emission rate. The rule should clarify whether the

demonstration is to be submitted to the GRIC or provided upon request.

Section 4 on recordkeeping should clarify how long records should be maintained. Consistent with CAA Title V and the federal statute of limitations, we recommend that records be maintained for five years.

B. Aerospace Man ufacturing

Rule Summary

Part VII, Section 2 .0 controls VO C emissions from aerospace manufacturing or rework facilities within the exterior boundaries of the Gila River Indian Community.

This rule establishes VOC emission limits on primers, topcoats, che mical milling maskants, and specialty coatings. As an alternative to meeting the applicable coating limits set forth in the rule, the owner or operator may comply by operating an emission control system with a combined VOC emission capture and control effi ciency of at least 81% by weight.

Another alternative to meeting the coating limits is using the averaging provision stated in section 4.1.A. The averaging provision can only be used with coatings listed in table 1 of the rule (categories of primers, t opcoats, and maskants) and cannot be used in specialty coating categories (section 5.2). EPA has assumed the averaging period to be 30 days because section 4.1.A describes monthly records and section 5.1 discusses a monthly mass

- weighted average. Also, w e have inferred from section 5.1 that the equation to determine compliance would be similar to those in South Coast Air Quality Management District (SCAQMD) Rule 1113 in Appendix A and Bay Area Air Quality Management District (BAAQMD) Rule 8

- 32 Manual of P rocedures, Volume I

Procedure 6.

In order to demonstrate compliance with the averaging provision, it is also necessary to keep appropriate and accurate records as listed in Section 4.1.A. The facility shall maintain a list of coatings used. The list mus t contain the category of the coating, noncompliant compounds, VOC content as applied, and monthly usage amount. When using the averaging provision, additional information such as the calculation records

should also be retained.- 14

-

Rule Evaluation

The B luebook ( Issues Relating to VOC Regulation Cutpoints, Deficiencies, and

Deviations , EPA, May 25, 1988) and the Little Bluebook ( Guidance Document for Correcting Common VOC & Other Rule Deficiencies, EPA Region 9, August 21, 2001) were used to help evaluate the rule for enforceability. The monitoring, recordkeeping, reporting and other requirements generally ensure that the submitted

rule can be enforced.

We have also considered the guidance document Improving Air Quality with Economic Incentive Programs (“EIP”, EPA, January 2001) in evaluating the averaging provision in

section 5.1. We have identified several elements of Section 5.1 that are inconsistent with EPA’s EIP guidance and have discussed them briefly below in the section describing recommendatio ns.

T he Control Techniques Guideline for the Control of Volatile Organic Compound Emissions from Coating Operations at Aerospace Manufacturing and Rework Operations (Aerospace CTG) EPA/OAQPS December 1997 was used to evaluate the rule’s stringency.

Recom mendatio ns f or Rule Improvement

The following revisions are currently not the basis for rule disapproval, but are

recommended for the next time the rule is amended.

Section 1.2

– The rule has several exemptions that are not recommended in the Aerospace CTG. The CTG does not list "chemical milling," "electrodeposition," "composite processing," "electronic parts and assemblies," "manufacture of aircraft transparencies," and "wastewater treatment operations" as exemptions. Also, exemptions such as "metal f inishing" and "manufacturing and rework of parts and assemblies not critical to the vehicle's structural integrity or flight performance" seem broad and may make the rule difficult to enforce. Removing some or all of these exemptions, or defining them more narrowly, will improve enforceability and may

result in additional emission reductions.

Section 3.1

– Emission limits are consistent with the Aerospace CTG, but do not approach those achieved by SCAQMD Rule 1124 and other analogous state and local

rules. More stringent emission limits could help further reduce emissions from aerospace manufacturing and rework operations.

Section 3.4

– The rule allows for other coating application methods not listed in this section, as long as they achieve emission redu ctions equivalent to high volume low pressure ( HVLP ) or electrostatic spray applications techniques. To strengthen the enforceability of this provision, an additional test method should be added to determine transfer efficiency. An example of such a test method is the SCAQMD- 15

-

method "Spray Equipment Transfer Efficiency Test Procedure for Equipment User, May 24, 1989."

Section 5.1

– Table 1 limits are allowed to average across coatings (primer, topcoat and maskants) to comply with limits on a monthly basis

. The following

recommendations to improve the enforceability of rule are based on guidance in the

Little Bluebook and the EIP document.

 The rule should include the calculation procedures (usually in the form of an equation) for determining compliance with the rule.

 Depending on the calculation procedure, the monitoring, recordkeeping, and reporting provisions may need to be revised to ensure that the rule requires recordkeeping sufficient to determine compliance.

 The rule should specify the averaging per iod, justify the averaging period, and demonstrate that the averaging period is consistent with attaining, maintaining the NAAQS, meeting progress requirements, and ensuring equivalency with RACT. Averaging Times for Compliance with VOC Emission Limits

– S IP Revision Policy

, memo from John R. O’Connor, EPA/OAQPS, January 20, 1984 has more details on what information is necessary when justifying an averaging period longer than 24

hours.

 To improve the environmental benefit s achieved by the rule, we suggest s etting

the emissions limitation at 90% of what otherwise would have been the limit without averaging.

 The rule should specify that if there is a violation of the averaging provision, each and every day within the averaging period is a separate violation. I.e., unless otherwise demonstrated, a violation of a 30

- day averaging provision results in 30 separate violations.

C. Nonmetallic Mineral Processing

Rule Summary

Part VI, Section 3 .0 controls volatile organic compound (VOC) emissions from cutback aspha lt and particulate matter emissions (PM

- 10) from sand and gravel facilities.

Rule Evaluation

The Bluebook ( Issues Relating to VOC Regulation Cutpoints, Deficiencies, and

Deviations , EPA, May 25, 1988) and the Little Bluebook ( Guidance Document for

Cor recting Common VOC & Other Rule Deficiencies, EPA Region 9, August 21, 2001) were used to help evaluate the rule for enforceability. The monitoring, recordkeeping, reporting and other requirements generally ensure that the submitted

rule can be enforced.

A part of the Gila River Indian Community is a serious PM

- 10 non

- attainment area. Sand and gravel facilities operate in this portion of the Gila River Indian Community. We are proposing to treat the nonattainment area requirements of part D, title I of- 16

-

the Act as not applicable to the TIP because the TIP (including its rules) are reasonably severable from part D requirements. We note, however, that this rule does not meet BACM since it is less stringent than several analogous rules in other areas, includin g South Coast Rule 1157 and Maricopa County Rule 316. See the “Additional Recommendations” section below for examples of how analogous rules are more stringent.

Recommendations f or Rule Improvement

The following revisions are currently not the basis for rule disapproval, but are

recommended for the next time the rule is amended:

 Unlike SCAQMD Rule 1157 and Maricopa Rule 316, Section 3 does not contain requirements for storage piles, unpaved roads and track out.

 Unlike SCAQMD Rule 1157, Section 3 does no t contain a prohibition for any visible fugitive dust plume to exceed 100 feet in any direction from any activity, equipment, storage pile or disturbed surface area.

 Unlike Maricopa County Rule 316, Section 3 does not require watering systems be operated in order to maintain a 4% minimum moisture content.

 We note that the applicability section of the rule refers to the use of cutback asphalt and VOC limits , but that th e rule appears generally to regulate PM

emissions from nonmetalli c mineral mining and p rocessing operations

. We

recommend cla rifying the scope and applicability of this rule

.